Spray from Lake Erie and below-freezing temperatures turned Cleveland's West Pierhead Lighthouse into a Popsicle last week, leaving the Coast Guard to worry that any stubborn skippers braving the lake this time of year would miss the shoreline. The light's lens, as well as the rest of the building, is completely iced over—and will be for months.

Mariners have been issued warnings to exercise extra caution around the harbor entrance, though most boat traffic has already stopped for the season, said Petty Officer 3rd Class George Degener, who serves with the U.S. Coast Guard's Cleveland-based Ninth Division.

On the bright side: There's no lighthouse keeper shivering inside the icy tower. The facility has been automated for decades.

High winds and a few solid weeks of below-freezing temperatures have caused multiple layers of frozen spray to build up on the 67-foot-tall (20-meter-tall) West Pierhead Lighthouse, seen in a December 19 picture taken by National Geographic My Shot user David Sands.

"People think, Oh, it's just a lake, and it doesn't have that much weather," Petty Officer Degener said. "But with the size of the body of water we have here and the extreme weather, the seas can reach 8 to 10 feet [2.4 to 3 meters] high in a short period of time," Degener said.

The fourth largest of North America's five Great Lakes, Lake Erie (map) recahes a maximum width of 57 miles (92 kilometers).

Seen in a September 2008 picture taken by National Geographic My Shot user Ella Spiri, Cleveland's West Pierhead Lighthouse looks much like any other lighthouse. But come winter, it and other Great Lakes lighthouses sometimes turn into fairy castles, birthday cakes, or whatever wintry description best fits.

Ice buildup on Great Lakes lighthouses are not uncommon. "You're going to get ice buildup whenever the weather is this way," Degener said. But the 2010 freeze-out happened much earlier, because frigid temperatures arrived sooner than usual.

The extent of the freezing in 2010 is also exceptional. It's rare for ice to coat a lighthouse so thoroughly that the light is no longer visible.